Means for resiliently mounting vanes or frangible pump elements



Jan. 5, 1954 s. G. ORBAN 2,665,056

MEANS FOR RESILIENTLY MOUNTING VANES OR FRANGIBLE PUMP ELEMENTS FiledJune 20, 1951 2 Sheets-Sheet 1 INVENTOR.

STEPHEN a. ORB/4N BY my Jan. 5, 1954 Filed June 20, 1951 MEANS FO s. G.ORBAN 2,665,056 R RESILIENTLY MOUNTING VANES FRANGIBLE PUMP ELEMENTS 2Sheets-Sheet 2 JNVENTOR.

STEPHEN G. ORB/4N Patented Jan. 5, 1954 MEANS FOR RESILIENTLY MOUNTINGVANES OR FRANGIBLE PUMP ELE- MENTS Stephen G. Orban, Bloomfield, N. J.,assignor to Bendix Aviation Corporation, Teterboro, N. J., a corporationof Delaware Application June 20, 1951, Serial No. 232,512

4 Claims.

This invention relates generally to means for appyling a spring force toa relatively soft, frangible element or body and more particularly hasto do with a novel saddle-like button arrangement interposed between aspring and an element made of carbon, graphite or other relatively softand frangible material whereby the force exerted by the spring may betransmitted to the elemen The instant invention has particular utilitywhen employed to maintain the sliding vane of a dry air rotary pump inoperative contact with the rotor thereof.

It has become common practice to utilize sliding vanes made of graphite,or carbon, in dry air rotary pumps, especially where such pumps aredesigned and constructed to operate at relatively high speed.

Due to the relatively soft and frangible character of the material ofsuch sliding vanes, the

spring loading of the vane so as to maintain it in tinued positiveoperation of the pump. In other instances, where a resilient pad hasbeen interposed between the end of the spring and the vane, the hightemperatures developed during the operation of the pump have resulted inthe rapid deterioration or breakdown of the pad. Moreover, the use of aresilient pad has also been found objectionable in that in instanceswhere the bonding agent securing the pad to the vane fractures, the pad,being resilient, does not provide a stable platform between the springand vane with the result that the vane is apt to shift or move out ofalignment with its guides. It is apparent under such conditions the vanemay break or wear unevenly, thereby resulting in the breakdown orinefficient operation of the pump. The instant invention has for one ofits objects the provision of means for mounting the carbon or graphitevane of a rotary pump so as to overcome the foregoing difficulties.

Among other objects, the present invention contemplates a vane assemblyembodying novel means whereby the vane may be operatively positionedrelative to the rotor of the pump and in the event the bonding agentsecuring the vane to the assembly fractures, the vane will be supportedin its proper position without any undesirable shifting or moving of thevane relative to the guides thereof.

A further object of the instant invention is to provide a stablemounting platform for a carbon or graphite element whereby a springforce may be transmitted to the element.

The above and other objects and features of the present invention willappear more fully hereinafter from a consideration of the followingdescription taken in connection with the accompanying drawings whereinone embodiment of the invention is illustrated by way of example. It isto be expressly understood, however, that the drawings are forillustration purposes only and are not to be construed as defining thlimits of the invention.

In the drawings wherein like reference char acters refer to like partsin the several views:

Fig. 1 is a fragmentary side view, partially in section, of a rotary airpump embodying the novel means for mounting the vane as contemplated bythe instant invention;

Fig. 2 is a fragmentary end view showing a vane assembly in elevationand its relationship with the rotor of the pump;

Fig. 3 is an enlarged section through the vane assembly;

Fig. 4 is a plan view of the vane; and

Fig. 5 is an enlarged side view of the saddlelike button.

Referring now to the drawings, Fig. 1 illustrates a rotary dry air pumpof a conventional type consisting, in general, of a power unit [0 and anair pumping assembly i l constructed and arranged to be mounted to, anddriven by, the power unit Iii.

In this instance, power unit it comprises an electric motor i2 suitablymounted and enclosed within a hollow housing it. An end wall It, closingone end of housing i3, is provided with an extension it in which ismounted an electrical connector or plug IE3 whereby the power unit illmay be connected into a suitable electrical circuit for the operation ofmotor 12.

The air pumping unit I 1 comprises a casing 3! having head and end wallsI8 and i9, respectively, that are adapted to be mounted to oppositesides of casing ll. Head wall I8 is secured to the casing I? by bolts 20which pass through registered openings in a flange 2| and a flange 22formed integrally with casing ll and head wall l8, respectively.

In order to mount the pumping assembly H to-the power unit 10, end wallI9 is provided 3 with a lateral extension 23 that extends partially intothe open end of housing l3. A snap ring 24 is engaged within an annularrecess 25 formed in housing 3 adjacent its open end, and a bearing ring26, slidable within housing I3, is adapted to engage the inner urface ofthe snap ring 24'. A series of bolts 21 pass through registered openings provided in bearing ring 26, end wall l9 and a flange 28 formed oncasing I! to the end that the tightening of nuts 29 carried by bolts 21brings the bearing ring 26 intoengagement with snap ring 24 therebysecurely mounting the casing I! to the housing 3.

Head and end walls I8 and I8, respectively, operate with a bore formedin casing-ll to define a cylindrical pump chamber 30. Motor 2 isprovided with a shaft 3| that extends through alcentral opening 32 inend wall l9 and across pump chamber 30, where it is journalled in asealed Suitable bearing 33 mounted in head wall l8. seals 34- areprovided to prevent any lubricant utilized in bearing 33iromleaking1intothe pump chamber 30.

An eccentric rotor 35 is secured to shaft 31 for rotation therewith andcarbon seals 36and 31 tively, with a bore 44 formed in casing-|l'intermediate the passageways Wand 4|. A slot 45 formed in casing 11between bore-44- and pump chamber 3|] communicates the former with thelatter.

Bore 44 is adapted to receive a'cylindrical insert 46 havingangularlydisposed, fl'at'side surfaces and. 48 and a vertic'al'sl'ot 49."A" vane 50 slidably mounted in slot extends through slot 45 and isadapted at its end 51 to' sealingly contact the rotor 35. Thus,-vane-50' divides slot 45 into passageways 45a and 45b which" communicatewith inlet and outlet passageways 40 and 4| respectively.

In order to. apply a resilient pressure to the vane 50 and therebysealingly. engage the enjdjl thereof with rotor 35, a plurality ofspring assemblies, generally indicated by the reference character 53,are mounted in casing I! and are disposed so as to engage, the vane 50at spaced intervals along the lengththereof. As shown in Fig. 1, theinstant pump assembly is provided with two spring assemblies 53, andsinceeach spring assembly 53 is identicalin-structure, only one isdescribed in detail.

. To house the spring assembly 53, casing Hand insert 46 are providedwith registered, vertical bores 54 and 55, respectively; A cover plate56, removably mounted to casing by-a bolt 51-, has fixedly securedthereto a stud or post 58 that is adapted to be snugly received intovertical bore 54. To preventleakage through bore 54, post 58 is providedmedially of its length with an annular groove 59 in. which: is mounted arubber sealing. ring 60. The inner end of post-58 serves as a seat forone end of a. compression spring 6| that is utilized to apply therequired resilient load to vane 50.

As above set forth, the engagement of the other endof spring-6| toivaneill-has heretofore presented many'probl'ems Thus; where spring 6| hasbeen placed directly in contact with vane 50, the relative hardness ofthe materials has resulted in a rapid breakdown of the vane and where aresilient pad has been interposed between the spring BI and vane 50 thehigh operating-'temperatureand frequent-breaking of the bonding agenthas similarly. resulted in inefiicient pump operation.

.The instant invention overcomes the difliculties heretofore experiencedby providing a novel saddle-like button 62 that is adapted to beinterposed between the spring 6| and vane 50 and which serves totransmit the pressure from the former'to the latter.

As shownin Figures 3 and the saddle-like button 62- comprises acylindrical body 63 having diametrically opposed, depending flanges 64which define a transverse channel 65, substantially U shaped incross-section, at one end of the body 63. The channel 65 is dimensionedso as to receive one endof: the vane:50 :thereimwith the end of the vane5|) in abutment with the transverse wall of channel 65 and with'the-interior surfaces of flanges 64 snugly embracing the opposite sidewalls of the vane 50. The body 63 may be centrally recessed as at; 66andascenrtral aperture 61 extending betweenthe channel 65 and recess 66is adapted toreceive shank 68 of a rivet orstud69. Rivet 69is'securedto-body 63 by upsetting the end-of theshank'68thereof,

or by some suitable-bonding 'agent: A- convexa head formed on rivet 69is thereby: positioned, in channel 65 between the flanges 64, where itengages a concave recess or depression. shown in Fig. 4- and formed inthe upper surface" of: the vane 50'; A suitable bonding-agent, such as.sodium silicate, applied to the inner: surfaces of flanges 64 andtheconvex head 10 of rivet 69 serves to securely fasten the 'body 63 tothe vane 50.

Medially of its length; the'body-63 is provided with an annularperipheral flange 1-3 whichforms a seat for-the lower "end of spring 6|.Thus, spring 6| is operativelypositioned between the lower-end of post58' and-*the flangela of the saddle-like button 62;

It will be seen'from the-foregoing description that all that isnecessary to carry out the teaching of the instant inventionis thatthe's'addlelike button 62 have a channel for-the reception orvhousing'of the upper end of the vane 50;- that therebe providedacooperating' abutmen'tlil and depression "formed in the-channel andvane, and a means 13, for seating the spring-in engagement with thesaddle-like; button 62.

Due to'theforegoing arrangement ofparts, when. motor 12, is actuated torotate the rotor 35, in a clockwise direction as viewed in- Fig; 2, airis drawn intothe pumping'unit 'H throughthe inlet provided-in head'wallI8; From the inlet, the airpasses through-inlet passageway 40' and duct42,- into bore 44-Wheresurface -41 -deflects the air throughpassagewayiiai-into the pump chamber 'Airbeing discharged-frompumpchamber 3 6 by-the rotor leaves through. passageway. 451) where itisdeflected. by: surface 48: through. duct 43 =into outlet/passageway 4|and from thenceto outlet: 39. Ajonewaytflapper valve 15 operatively:positioned in outlet ,3 9 per-- mits air under pressure of the pumpto-pass from the. outlet while; preventing back flow of air intothepumping unit As hereinbefore set forth,- the vane is re-.- silientlyurged into contact withrotor 35 It. is apparent, therefore, that as theeccentric rotor.

35 revolves, spring assemblies 53 operate to maintain the end 5| of vane50 in sealing contact with the rotor 35 to the end that communicationbetween passageways 45a and 45b is prevented.

In the event the bonding agent securing the saddle-like button 62 tovane 59 fractures or fails in any way, the flanges t4 prevent anytransverse movement of the saddle-like button 62 relative to the vane50, while the engagement of the convex head of the rivet 69 with theconcave recess H formed in vane 50 prevents any longitudinal movement ofvane 50. The saddle-like button 62, therefore, forms a relatively stableplatform through which the force exerted by spring 6| is transmitted tothe vane 50. Thus, it is apparent that vane 50 continues to reciprocatein slot or guide 49 without shifting or canting relatively thereto andthe pump assembly H continues to operate Without loss of efiiciency.

From the foregoing description of the construction and operation of thepresent invention, it will be apparent that a novel means formaintaining the sliding vane of a rotary type dry air pump in sealingcontact with the rotor thereof has been provided in which the severalobjects of the instant invention have been achieved.

I claim:

1. The combination with a relatively soft frangible element and a springfor applying a force to said element, of a button adapted to beinterposed between said element and spring for transmitting forceexerted by the spring to the element comprising a body, dependingflanges on said body defining a U shaped channel at one end of said bodyfor the reception of said element, said flanges serving to preventtransverse movement of said element in said channel, a convex abutmentin said channel, a concave recess in said element for engagement withsaid convex abutment to prevent longitudinal movement of said element insaid channel, and a peripheral flange on said body for engagement withsaid spring.

2. In a pump having a rotor; the combination comprising a vane slidablycontacting said rotor, a plurality of springs for maintaining the vanein contact with the rotor of said pump, a plurality of saddle-likebuttons; each of said buttons secured to one end of said vane andengaged by an end of one of said springs, each of said buttons includinga cylindrical body, depending flanges on diametrically opposed sides ofsaid body defining a transverse channel at one end of said body tosnugly receive one end of said vane, a peripheral flange on the bodymedially of its length for engagement by said one end of said spring,and a convex abutment mounted in said channel; said vane having aplurality of concave recesses formed in said one end of said vane, andthe convex abutment of each button engageable in one of said concaverecesses, and bonding means in the channel of each of said buttonssecuring said vane in said saddle-like buttons.

3. The combination defined by claim 2 in which each of said saddle-likebuttons includes a recess formed in its cylindrical body at the oppositeend from said flanges, a central aperture extending between the recessand the channel defined by said flanges, a rivet having a shank and aconvex head, said rivet being mounted in said body into the shankthereof in said central aperture and the convex head thereof in saidchannel so as to engage in one of the concave recesses formed in saidone end of the vane.

4:. In combination, a rotor, a vane having one end slidably contactingsaid rotor and a concave recess formed in the opposite end thereof, asaddle-like button comprising a cylindrical body, depending flanges ondiametrically opposite sides of said body forming a transverse channelat one end thereof to snugly receive said opposite end of said vane andprevent transverse movement of said vane relative to said body, a convexabutment in said channel and engageable with the concave recess formedin the end of said vane to prevent longitudinal movement of said vane insaid channel, a peripheral flange on said body disposed medially of itslength, and resilient means engageable with said peripheral flange formaintaining said body in engagement with said vane and said vane incontact with said rotor.

STEPHEN G. ORBAN.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,254,781 Babbitt Sept. 2, 1941 FOREIGN PATENTS Number CountryDate 219,650 Great Britain Feb. 12, 1925 346,020 Great Britain Mar. 30,1931 66 .599 Germany Oct. 18, 1935

